1. Field of the Invention
The present invention relates to a sample analyzer which performs elemental analysis of a sample by irradiating the sample with a primary beam such as an electron beam and detecting a signal emanating from the sample such as characteristic X-rays.
2. Description of Related Art
A sample analyzer such as an electron probe microanalyzer (EPMA) can perform compositional analysis (elemental analysis) of elements present on the surface of a sample by irradiating the sample with an electron beam (primary beam) and detecting characteristic X-rays emanating from the sample.
In this case, a two-dimensional analysis of elements constituting the sample (measurement of a two-dimensional distribution) can also be performed by scanning the electron beam over the sample.
In this two-dimensional analysis, a concentration map of each element to be analyzed can be obtained based on a previously found relationship between the detected intensity of characteristic X-rays and mass concentration. Furthermore, a phase analysis for identifying compounds contained in the sample can be performed by finding the distributions of concentration ratios of the elements.
Where three elements are specified from several elements to be analyzed, the distributions of concentration ratios of the three elements can be represented as a ternary scatter diagram by plotting data in a graph based on obtained data about concentration distributions of the elements. Information plotted in this ternary scatter diagram permits identification of compounds contained in the sample.
One example of such a ternary scatter diagram is shown in FIG. 6 of JPA-2006-125952.
In the ternary scatter diagram based on the conventional technology, only concentration distributions of specified three elements can be represented.
In order to obtain more detailed information about the sample, it may be desired to refer to concentration information about elements other than the specified three elements, in addition to concentration information about the three elements.